Walkability is becoming a popular buzzword in planning cities that suffers high level of pollution due to, amongst others, emission from automobiles are embracing walkability in order to reap its benefits. In addition to that, walkability is the measure of how satisfactorily the transportation system meets the need of walking of the community. Several studies around the world have put great efforts to highlight the importance of walkability in urban as it is an important measure in determining a better environment. There is a strong relationship between walkability, sustainable transportation and the environment. In addition to that, walkability is a concept that is consistent with sustainable development and transportation system due to its economic, social and environmental benefits. Walkability satisfaction rating within a localized neighborhood can be measured at the macro level with the aid of GIS at the initial development stages. The methods and techniques used are varying and no single walkability assessment tool can be designed to suit different environmental conditions. Different groups of societies for whom the theoretical and practical perception of cities development vary, or different types of neighborhoods with different needs would warrant different approaches. Therefore, this paper examines the methods, techniques and indicators that have been used to measure walkability and highlights the important benefits of improving walkability in the built environment. Moreover it also describes the relationship between walkability, sustainable transportation and environment.

Malaysia has committed to reduce its greenhouse gas (GHG) emissions by up to 40% by the year 2020. The fact that transport sector of Malaysia shares a big portion of national GHG emissions; its role is paramount. The present study reviews the current state of GHG emission, the major technical and policy measures that can be adopted, and the measures that have been initiated in Malaysia for GHG emission reduction in transportation sector. Data related to road vehicles and GHG emission from road transportation are collected from open source databases and analyzed to reveal the present trends and possible future changes in GHG emission due to government initiatives. The result shows deceleration of GHG emission from transportation sector of Malaysia in recent years. However, the study reveals that the present measures may not be enough to reduce GHG emission up to the set target. Malaysia needs more prudent strategies for climate-friendly development of transportation to achieve sustainability goals. The study also examines the potential of Malaysia to reduce GHG and the measures that that can be initiated to streamline the effort towards GHG emission reduction are discussed.

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Despite the several benefits of modifying bitumen with polymer; it is increasingly becoming difficult to ignore concerns about its high energy consumption and fume emissions during asphalt production. Previous studies found on natural rubber (NR) modified binders applied it as a hot mix asphalt (HMA), however in recent years there has been increasing interest in warm mix asphalt. This research explores the possibility of applying NR in warm mix asphalt (WMA) by comparing the physical properties of cup lump rubber modified bitumen with and without warm mix additive. Four percentages (2.5%, 5.0%, 7.5% and 10%) of Cup lump rubber (CLR) was used to modify 60/70 penetration grade bitumen, while three percentages (0.3%, 0.4%, and 0.5%) of Evotherm chemical was added to produce warm cup lump modified bitumen (WCMB). Storage stability, penetration, softening point, viscosity, ductility, and elastic recovery tests were conducted to determine the effect of CLR and Evotherm. The results show that storage stability and viscosity of the cup lump modified bitumen heavily depends on the CLR content. While a positive correlation exists between the increase in binder stiffness with increasing mixing and compaction temperatures. The addition of 0.5% Evotherm reduces the viscosity by 14%. Contrary to expectations, CLR was found to reduce the ductility of the bitumen while the presence of Evotherm in the blend increases the softening point. The use of warm NR modified bitumen in road construction is expected to lower the asphalt production temperature, carbon emission and cost without compromising the performance of the mix.

This paper evaluates the sustainability of traffic growth in Malaysia.The number of registered vehicles is used as an indication of traffic growth.Also, the number of registered buses is considered as an indication of public transportation usage. The results indicate that the traffic growth is mainly due to increases in the private cars motorcycles, while the rate of increase for buses is very small.The percentages for passenger cars and motorcycles are increasing while the percentage of buses is slightly dropping down, which is a negative indication regarding the traffic growth in Malaysia. The trends for the rate of vehicles per capita, unit GDP, and unit length of the road network have been discussed. Most of the trends indicate that the current growth trends of traffic in Malaysia are unsustainable. The paper also provides some recommendations for the Malaysian government to maintain a sustainable traffic growth in the country. 